peterson



E. F. PETERSON BLIND END CORE BOX BLOW TUBE Aug. 18, 1959A 3Sheets-Sheet 1 Filed Aug. 29, 1955 Aug, 18, 1959 E. F. PETERSON BLINDEND CORE BOX BLOW TUBE 3 Sheelcs-Sheet 2 INVENTOR. ZZm/z f. [Je'ensoaFiled Aug. 29, 1955 INVENTOR.

3 Sheets-Sheet 3 Tf-"152 E. F. PETERSON BLIND END CORE BOX BLOW TUBEyAug. 18, 1959 Filed Aug. 29, 1955 a l. Q... A nn n n n... l .f 5V? .l M.v l l f P www k NN nited Stats BLIND END CORE BOX BLOW TUBE Edwin F.Peterson, Neponset, Ill.

Application August 29, 1955, Serial No. '530,961

3 Claims. (Cl. 22-10) This invention relates generally to sandconducting tubes of the character used between a core sand supply sourceof a core blowing machine and a core box and to a method of making sandcores.

More specifically the blow tube of the present invention is directed toa composite structure blow tube for conducting sand into a core box froma sand supply box and` which comprises a new and novel construction in apredetermined arrangement of metal and wear resistant parts that areapertured to produce a new and desirable result in making sand cores ina core making machine.

It has been one of the objectionable features in prior practice in coremaking that the blow tubes were definitely directional in their sanddischarging capacities with resulting damaging wear to core boxes andparticularly tothe areas disposed in the path of the discharging coresand stream in core boxes. This holds true whether blow tubes areemployed or whether sand conducting bores were used to direct the sandinto the core boxes.

Although there were various means devised to counteract such undesirablewear in core boxes, such remedial means were at best expensive and addedconsiderably to the cost ofthe original core box constructions. One sucharrangement is shown in my Patent No. 2,659,119 issued on'November 17,19,5 3.

It is one of the objects of the present invention to devise a blow tubeof a new and novel arrangement that will efficiently and fully fill acore box with core sand 'and which will eliminate the use ofconcentrated sand streams to definitely increase and prolong the life ofa conventional construction of core box without adding to the normalexpense of manufacturing such a unit or to the maintenance thereof.

It is another object of the present invention to provide va closed orblind end core box blow tube which will definitely prevent directdischarge of core sand against y'an opposite surface of the core boxthat is disposed in Kthe normal axial direction of the sand blowingtube.

As afurther object the core box blow tube of this "invention is providedwith a closed end rubber tip arranged,with one or more radially disposedopenings that function "todivide the main sand stream under pressure.into a plurality of. streams that are directed generally radially ofthe tube and laterally within a cavity of a core box using the presenttube.

l Y Still other objects of the present invention are to provide variousforms of openings that are radially disposed about, the resilient end ofthe blow` tube to establish dir'lected4 radial l distribution of thecore sand coming v'thrfuglgi tlie'gblow ,tube from the core sand supplysource. And as another object of the present invention a sand core isformed through a method using coacting opposed Isand streams in a corebox cavity that createa compact sand core quicklyv without core boxwear.

Thenblow tube of the present invention is constructed alsdshownA in the.preferred embodiments disclosed so AastoEbegfmorespecifically adaptedfor use in discharging dry fully owablesand or 'for' the otherconventional ice lmixes of green strength sands used in making sandcores in the core making industry. In other words, the tubes must becapable of handling core sand ranging from hour glass sand to very toughand gummy mixtures.

Other objects and advantages relating to the core box blow tube of thisinvention shall hereinafter appear in the following detailed descriptionhaving reference to the accompanying drawings forming a part of thisspeciication.

In the drawings:

Fig. 1 is a vertical cross sectional view of `a functional arrangementof sand blowing head of a core making machine or the like servicing acore box, this arrangement incorporating a sand blowing tube constructedaccording to the principles set forth by the present invention;

Fig. 2 is a plan sectional view of the core box arrangement illustratedin Fig. 1, but as Viewed substantially along the plane of the line 2-2indicated in Fig. 1;

Fig. 3 is a vertical cross sectional View taken axially of the blow tubeillustrated in Fig. 1 to show certain details of the constructionthereof;

Fig. 4 is a tnansverse cross sectional view taken substantially alongthe plane of the line 4 4 in Figure 3;

Fig. 5 is another transverse cross sectional view taken lsubstantiallyalong the plane ofthe line 5-5 indicated in Fig. 3; y

Fig. 6 is a side elevational view of a modified form of blow tubeincorporating the principles of the present invention; 'n

Fig. 7 is a vertical cross sectional view taken substantially along theplane of the line 7-7 in Fig. 6 showing certain parts of the tubedisposed in operative positions;

Fig. 8 is a plan sectional view taken transversely of the blow tube inFig. 6 andsubstantially along the plane of the line 8--8 therein;

` Fig. 9 is a fragmentary side elevational view of the discharging endof a blow tubeillustrating another form of the present invention and asthis tube appears when inert and without pressure acting within'thetube;

Fig. 10 is another side elevational view as Fig. 9 generallyillustrating the appearance of the tube when subjected to core sandunder pressure and as it appears in its operative sand dischargingcondition;

Fig. 1l is a plan sectional View taken transversely of the tube shown inFig. 9 as viewed substantially along line 11-11 therein; y v

Fig. 12 is la fragmentary View of a portion of a formed core developedby the sand tube of the present invention and for purposes of furtherexplanation of the use of the present sand blowing tube.

Fig. 13 is a vertical cross sectional view taken through a core boxsetupy using opposed sand stream discharging tubes providing a new andnovel method of forming a sand core unit;

Fig. 14 is a sectional view of a ask providing a mold that receives thesand core formed according to Fig. l, and further illustrating thedisposition of the blow tubes to leaveimpressions in the core printsections of the sand core;`and

Fig. 15 is a fragmentary cross sectional View taken substantially alongthe line 15-15 indicated in Fig. 14 to show further details ofconstructionas employed.

l Referring to Figs. 1 and 2 the construction herein illustratedconsists of a two piece core box 1 comprising one or more Vuppersectionsv 2 and one or more lower sections 3 outlining a core formingcavity 4 with the sections being matched along the parting line 5 of thecore box to provide the means to produce a core of a predeterminedperipheral contour as is the normal practice in core making. The corebox sections 2 and 3 are clamped to the adjustable supportingtable'6.,a1 id to the blow plate 7 of the core sand supply box 8,respec- 3 tively. Box 8 contains the usual supply of core sand 9 whichmay be either of dry sand consistency or of green sand consistencydepending upon the specic conditions of use. One of the sections 2carries air vents 2a and vent plugs 2b as is the usual practice.

The blow tube of the present invention is illustrated generally at 10and this tube has its upper end 11 secured within a close fittingopening 12 in the blow plate 7 and the tube projects through an opening13 formed in the upper wall 14 of the upper section 2 of the core box 1.It should be noted that the lower end or tip 15 of the blow tubeprojects downwardly into the chamber 4 a predetermined amount to carryout the sand blowing operation of the present tube construction.

Referring now more specifically to Figs. 3, 4 and 5 the blow tube of thepresent construction comprises a composite unit having a metal tubesection 16 and a wear resistant or rubber tube section 17 which sectionsare xedly bonded together at 18 through the interrelated annular flangeconstruction shown in Figs. 3 and 5. It should also be noted that themetal tube 16 and the extended portion comprising the wear resistanttube section 17 are of identical thickness with the inner and outerwalls of both being contiguous and smooth as best shown in Fig. 3.

The wear resistant or rubber section 17 comprises a closed or dead endconstruction having a solid radial or transverse wall 19 closing off theblow tube at the very location that is normally open for full streamsand discharge as is normally done with blow tubes now used in the coremaking industry. Spaced upwardly from the closure wall 19 are one ormore radial openings 20 formed about the periphery of the dead endrubber tube section described.

With a tube of this construction it is possible to use and feedreasonably dry granular sand or the usual green core making sand becausein either case the sand will be trapped in the bottom end of the tube bythe dead end wall 19 thereof building up a flow stop resistance. Withthe air pressure relieved, very little if any of the dry sand would feedout of radial openings so that this tube can be employed to dischargevarious types of sand used in the operation of a core making machine.

The tube of the described construction is installed and used in themanner shown and illustrated in Figs. l and 2. Here the bottom tip end15 of the tube projects below the upper inner surface 21 of the upperwall 14 of section 2 of the core box to bring the one or more radialopenings of the rubber section 17 into clearance positions within thecavity 4 of the core box 1.` The core sand under pressure may now be fedin one or more streams such as 22 into the far reaches and connectedcavities of the core box until all of this sand is backed up to the tubelocation to completely lill the core box cavity 4.

With this particular action and distribution of the core sand dischargedby the blow tube 10 of the present invention the sand entry into a corebox is distributed over wide areas of the interior surface of the corebox to diversity and minimize the concentration of said feed and thus tosubstantially eliminate objectionable wear on the interior surfaces ofthe core box sections 2 and 3.

Referring to Figs. 6, 7 and 8, another form of blow tube is shown thatis constructed according to the principles of the present inventionwhich comprises a metallic tube 24 that is suitably bonded at 25 to arubber tip 26 in rnuch the same manner as the blow tube previouslydescribed and illustrated in Fig, 3. In the modified construction ofFigs. 6 to 8, the rubber tip 26 again includes a dead end wall 27 thatcloses off the end of the tube. Spaced upwardly from the dead end wall27 are one or more composite slit arrangements in reclining H forms asshown at 28 and 29 that divide circumferential wall portions of the tubeinto pairs of coacting doors 30-31 and 32-33. Y i

For example the slit arrangement 29 on the tube tip 26 illustrated inFig. 6 includes axially spaced transverse slits 34 and 35 joinedintermediate their lengths by a longitudinally placed slit or cut 36which forms a coacte ing door arrangement. Under normal inactiveoperative conditions the door units will be closed to retain sand withinthe tube. Under pressure conditions, however, this tube will operatewith open doors and discharge sand into the core box in the same manneras previously described in connection with Fig. l, but the sand will bedischarged through the door constructions 30-31 and 32-33.

The tube shown and illustrated in Figs. 9, l0 and ll includes a metalsleeve 37 and a rubber tip 38 having a dead end bottom 39. This tubearrangement provides longitudinally spaced rows of annularly formedslits 40, 41, 42 and 43 which are staggered circumferentially as shownin Fig, 9 and as further illustratedin Fig. `ll. This tube underpressure will normally be closed as shown in Fig. 9, but under theaction of sand under pressure introduced into the tube the rubber tip 38will expand endwise as shown in Fig. 10 to open the rows of slits 40 to43 inclusive to provide a multiplicity of radiallyvdisposed dischargeopenings for the multiple distribution of the sand into a plurality ofstreams leading radially outwardly from the rubber end of the tubedisposed within the core box cavity. v

Since the tubes of the present construction are disposed slightlyinwardly of the core box cavity as demonstrated in Fig. l a portion ofthe formed core shown at 44 in Fig. l2 will obviously include a smallindenture or recess which is indicated by the rectangular area 45 thatmay be easily patched with a core sand ll such as illustrated at 46. Itis also possible to plan the location of the core blowing tubes so as tobe within a dotted line area such as shown at 47 in Fig. l2 that may beprovided as a core print zone or core part. This will hereinafter bemore fully described.

Referring now to Figs. 13 to 15, an arrangement is here illustrated toform a sand core fin a core box through the method of providing opposedsand streams within the core box cavity. In Fig. 13 the core box 48consists of upper and lower sections 49 and 50, with section 49 suitablycarried by the blow plate 51 of the blow head 52 and with section 50clamped or otherwise secured to the table 53 of a core making machine.Cornplementary cavities 54 and 55 are provided in sections 49 and 50with air vents 56 and 57 formed in section 49 as shown, with vent plugs58 in vents 57.

Spaced blow tubes 59 and 60 are carried in aligned openings in the blowplate and core box as shown, each tube depending into the core boxcavity to a given distance with their tip ends 61 and 62. Also, eachtube, in this instance, is provided with one discharge opening such as63 in tube 59 and 64 in tube 60. These openings are arranged to faceeach other and are generally in line to direct opposite streams of sandtoward each other to meet at some given distance between the tubes andwithin the contines of the core box cavity.

Here the sand streams greatly act to neutralize the excessive abrasivesand action within the core box and also act to quickly fill up the boxin opposite corners or recesses and also form a central zone thereinforming a core such as 65 shown in Fig. 12 having the core print ends 66and 67.

Core 65 lends its use to a flask 68 as shown in Fig. 14 providing a moldwith a cope 69 and drag 70 together with a sprue cavity 71 andgate-cavity 71a all coacting to receive molten metal that is formed orcast into a reel or spool unit 72.

By positioning tubes 59 and 60 in spaced locations entering the coreprint forming cavities in the core box 48, cavities 73 and 74 resultwhich are well absorbed or concealed within the core print receivingcavities 75 and 76 found between the cope and drag mold sections of theflask 68. In this instance, recesses 73 and 74 need no patching andmerely comprise a part of the core as developed in the core makingmachine.

The foregoing description has been directed to several embodiments ofthe present invention and it is obvious that certain changes may be madeIin the individual elements of such constructions or in the combinationof such elements as described without departing from the fundamentalconcept of the invention. Such modications shall, however, be governedby the breadth and scope of the appended claimed subject matter directedto the present invention.

What I claim is:

1. In combination with a core box defining a cavity and having an upperWall containing an access aperture extending therethrough into anintermediate portion of said cavity, a sand conducting tube having arubber tip extending through said aperture and depending freely in saidcavity, said tip having a portion lying Within said aperture, a closedend lying within said cavity, and a portion lying within said cavitycontaining a radially disposed discharge opening spaced from said endand in communication with said cavity to direct sand radially outwardlyfrom said discharge opening into said cavity, whereby the introductionof sand under pressure through said tube tends to produce a seal betweensaid core box and tip.

2. The invention as set forth in claim 1 wherein said opening isexpansible in response to pressure applied within said tube.

3. The invention Aas set forth in claim 1 wherein said opening isdefined by at least one slit through said tip, adapted to distend inresponse to pressure applied Within said tube.

References Cited in the tile of this patent UNITED STATES PATENTS1,034,334 Bannister July 30, 1912 1,034,335 Bannister July 30, 19121,034,336 Bannister July 30, 1912 1,282,963 Shroder Oct. 29, 19181,695,855 Moore et al. Dec. 18, 1928 1,910,417 Zemon May 23, 19332,107,814 Billand Feb. 8, 1938 2,457,756 Vest Dec. 28, 1948 2,607,968Peterson Aug. 26, 1952 2,637,881 Peterson May 12, 1953 2,659,119Peterson Nov. 17, 1953 2,661,513 Brewer Dec. 8, 1953 2,761,186 PetersonSept. 4, 1956

